[src/trunk]: src/sys/uvm call pmap_growkernel once after the kmem_arena is cr...

[para <para%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/97b3ce286e39
branches:  trunk
changeset: 781458:97b3ce286e39
user:      para <para%NetBSD.org@localhost>
date:      Fri Sep 07 06:45:04 2012 +0000

description:
call pmap_growkernel once after the kmem_arena is created
to make the pmap cover it's address space
assert on the growth in uvm_km_kmem_alloc

for the 3rd uvm_map_entry uvm_map_prepare will grow the kernel,
but we might call into uvm_km_kmem_alloc through imports to
the kmem_meta_arena earlier

while here guard uvm_km_va_starved_p from kmem_arena not yet created

thanks for tracking this down to everyone involved

diffstat:

 sys/uvm/uvm_km.c |  37 +++++++++++++++++++++++--------------
 1 files changed, 23 insertions(+), 14 deletions(-)

diffs (80 lines):

diff -r 317dbfbec058 -r 97b3ce286e39 sys/uvm/uvm_km.c
--- a/sys/uvm/uvm_km.c  Fri Sep 07 04:50:35 2012 +0000
+++ b/sys/uvm/uvm_km.c  Fri Sep 07 06:45:04 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_km.c,v 1.134 2012/09/04 13:37:41 matt Exp $        */
+/*     $NetBSD: uvm_km.c,v 1.135 2012/09/07 06:45:04 para Exp $        */
 
 /*
  * Copyright (c) 1997 Charles D. Cranor and Washington University.
@@ -152,7 +152,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.134 2012/09/04 13:37:41 matt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uvm_km.c,v 1.135 2012/09/07 06:45:04 para Exp $");
 
 #include "opt_uvmhist.h"
 
@@ -202,7 +202,7 @@
 vaddr_t kmembase;
 vsize_t kmemsize;
 
-vmem_t *kmem_arena;
+vmem_t *kmem_arena = NULL;
 vmem_t *kmem_va_arena;
 
 /*
@@ -329,6 +329,18 @@
        kmem_arena = vmem_create("kmem", kmembase, kmemsize, PAGE_SIZE,
            NULL, NULL, NULL,
            0, VM_NOSLEEP | VM_BOOTSTRAP, IPL_VM);
+#ifdef PMAP_GROWKERNEL
+       /*
+        * kmem_arena VA allocations happen independently of uvm_map.
+        * grow kernel to accommodate the kmem_arena.
+        */
+       if (uvm_maxkaddr < kmembase + kmemsize) {
+               uvm_maxkaddr = pmap_growkernel(kmembase + kmemsize);
+               KASSERTMSG(uvm_maxkaddr >= kmembase + kmemsize,
+                   "%#"PRIxVADDR" %#"PRIxVADDR" %#"PRIxVSIZE,
+                   uvm_maxkaddr, kmembase, kmemsize);
+       }
+#endif
 
        vmem_init(kmem_arena);
 
@@ -782,18 +794,12 @@
 
 #ifdef PMAP_GROWKERNEL
        /*
-        * These VA allocations happen independently of uvm_map so if this allocation
-        * extends beyond the current limit, then allocate more resources for it.
-        * This can only happen while the kmem_map is the only map entry in the
-        * kernel_map because as soon as another map entry is created, uvm_map_prepare
-        * will set uvm_maxkaddr to an address beyond the kmem_map.
+        * These VA allocations happen independently of uvm_map 
+        * so this allocation must not extend beyond the current limit.
         */
-       if (uvm_maxkaddr < va + size) {
-               uvm_maxkaddr = pmap_growkernel(va + size);
-               KASSERTMSG(uvm_maxkaddr >= va + size,
-                   "%#"PRIxVADDR" %#"PRIxPTR" %#zx",
-                   uvm_maxkaddr, va, size);
-       }
+       KASSERTMSG(uvm_maxkaddr >= va + size,
+           "%#"PRIxVADDR" %#"PRIxPTR" %#zx",
+           uvm_maxkaddr, va, size);
 #endif
 
        loopva = va;
@@ -864,6 +870,9 @@
        vmem_size_t total;
        vmem_size_t free;
 
+       if (kmem_arena == NULL)
+               return false;
+
        total = vmem_size(kmem_arena, VMEM_ALLOC|VMEM_FREE);
        free = vmem_size(kmem_arena, VMEM_FREE);